Smoke appears in Washington subway system three times in two days

WASHINGTON (Reuters) - A mechanical failure on a Washington subway train caused smoke to fill a station stop on Sunday in the nation's capital, the third such incident in two days, according to officials.

He said officials were looking to see whether the failure was connected to a recent bout of wintry weather.

On Saturday evening, firefighters responded to a report of smoke and fire on a train line connecting Washington's Foggy Bottom station to a stop in Rosslyn, Virginia. The fire was caused by problems with system's electrified third rail, Stessel said.